Due to the advent of cable television, direct satellite systems, and other television program broadcast systems, television viewers have very large numbers of programs from which to select. Sophisticated systems have been developed to assist a viewer in selecting programs to view or record, among which are Electronic Program Guide, (EPG).
An EPG is an interactive, on screen equivalent to TV listings found in local newspapers or other print media. An EPG can provide up to 20 different kinds of information about each program that is within the time frame covered by the EPG. The time frame typically ranges from the next hour up to seven days in advance. The information contained in an EPG includes program identification information such as, program title, start time, end time, time remaining, topic, theme, actors, writer, production studio, awards, keywords, release date, director, and a brief description. EPG program information is usually displayed in a two dimensional table or grid format with time on one axis and channel number on the other axis.
Unlike non-interactive guides that reside on a dedicated channel and merely scroll through the current programming on other channels, EPGs allow viewers to select any channel at any time within the EPG's time range. Further, EPG features include the ability to highlight individual cells of the grid containing program information. Once highlighted, the viewer can perform functions pertaining to that highlighted program. For instance, the viewer could instantly switch to that program if it is currently being aired. Viewers could also program one touch video cassette recording (VCR) or the like if the television is properly configured and connected to a recording device. Such EPGs are known in the art and are described, for instance, in U.S. Pat. Nos. 5,353,121, 5,479,268, and 5,479,266.
U.S. Pat. No. 5,515,106, Chaney, describes a data packet structure necessary to implement an EPG system. The data packet structure is designed so that both the channel information (e.g., channel name, call letters, channel number, type, etc.) and the program identification information (e.g., content, title, rating, star, etc.) relating to a program may be transmitted from a program guide database provider to a receiving apparatus such as a television efficiently.
In a system capable of displaying an EPG, an electronic host device stores a record corresponding to each upcoming television program within the EPG's time frame. Each record contains program identification data that is unique to a particular upcoming television program. Program identification data includes at least one of program title, start time, end time, time remaining, topic, theme, actors, writer, production studio, awards, keywords, release date, director, and a brief description. Records are updated periodically by both deleting records of programs that have previously aired and adding new records of upcoming programs that fall within the EPG's time frame as time passes. The EPG is then displayed on a display module, such as a television, that is associated with the electronic host device.
EPG systems often store a large number of records for upcoming programs, facilitating an EPG to display a television programming schedule that covers a significant period of time. As such, an EPG can be used to find upcoming programs that may be of interest to a user days in advance of the program being aired. Thus, a need exists for a user to be able to efficiently and reliably search an EPG for upcoming programs that match a user's interests.
Methods and apparatus exist that allow a user to search an EPG system for records containing data that matches a user's search criteria, such as a text string. Some of the prior EPG systems may allow a user to perform, for example, a “one time” “search” or an “ongoing” search of the EPG records. In performing a one time search, a user composes a text string and a single search is conducted of the records for data matching the text string. Records containing data anywhere in the record that matches the text string are delineated as a match for that search. Once all the records are searched, upcoming programs whose records were delineated as a “match” are listed for the user in the display module's display area. As described above, the user can then perform a variety of functions pertaining to the listed programs by highlighting and selecting an upcoming program cell. An ongoing search is similar to a one time search except that the user-composed text string is saved in a nonvolatile memory of the electronic host device and repetitive searches are periodically performed of the records based on the saved text string. The repetitive searches can be performed either automatically or upon user command. One existing ongoing search is known as a Scout search.
One problem with prior art searches is that prior art search apparatus and methods search an entire record for data corresponding to the user-composed text string. As a result, records that contain data corresponding to the user composed text string anywhere in the record will be returned as a match. This results in a great number of “false alarms,” i.e., program records for upcoming programs that are of no interest to the user being returned as a match. For example, a search for the movie “Virus” would return as a match any and all programs whose titles, descriptions, themes, etc., contain the word virus. A search for the movie “Heavy Metal” would more often return music shows containing the term “heavy metal” in the description rather than the desired movie.
This problem is further aggravated by the additional information that is available in EPG records, including credit fields (actors, director, writer, studio, etc), awards information, and other miscellaneous information pertaining to a particular title, and by the ability to hold many days worth of guide information in the system. Continued implementation of prior art search mechanisms, therefore, will most likely return a much higher number of false alarms than hits, thus making the search feature less valuable to the user. Thus, there is a current need for an apparatus and method that searches EPG records more efficiently and reliably, resulting in less “false alarms.”